/Engine/Source/Editor/UnrealEd/Public/EditorViewportClient.h
Called to give the viewport client a chance to handle widgets being moved
virtual bool InputWidgetDelta ( [FViewport](API\Runtime\Engine\FViewport) * InViewport, [EAxisList::Type](API\Runtime\Core\Math\EAxisList__Type) CurrentAxis, FVector & Drag, FRotator & Rot, FVector & Scale )